CVE-2026-53667: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in remix-run react-router
React Router is a router for React. In versions 7.11.0 through 7.17.0, the RSCErrorHandler is missing protocol validation, allowing for redirects from untrusted sources. This issue is a follow up to CVE-2026-53667, and only affects consuming applications if they are using the unstable RSC APIs. This issue has been fixed in version 7.18.0.
AI Analysis
Technical Summary
CVE-2026-53667 is a CWE-79 (Improper Neutralization of Input During Web Page Generation) vulnerability in the remix-run react-router package. Specifically, in versions 7.11.0 through 7.17.0, the RSCErrorHandler component lacks protocol validation, which can lead to unsafe redirects from untrusted sources. This vulnerability only impacts applications that consume the unstable React Server Components (RSC) APIs. The issue was addressed and fixed in version 7.18.0.
Potential Impact
Successful exploitation can lead to high confidentiality impact by enabling attackers to redirect users to malicious sites, potentially leading to phishing or session hijacking. Integrity impact is low, and availability is not affected. The CVSS score is 6.9 (medium severity), reflecting network attack vector, high complexity, no privileges required, user interaction required, and scope change.
Mitigation Recommendations
Upgrade react-router to version 7.18.0 or later, where the vulnerability has been fixed. Since the issue only affects applications using the unstable RSC APIs, applications not using these APIs are not impacted. No other mitigations are specified.
CVE-2026-53667: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in remix-run react-router
Description
React Router is a router for React. In versions 7.11.0 through 7.17.0, the RSCErrorHandler is missing protocol validation, allowing for redirects from untrusted sources. This issue is a follow up to CVE-2026-53667, and only affects consuming applications if they are using the unstable RSC APIs. This issue has been fixed in version 7.18.0.
CVSS v3.1
Score 6.9medium
Affected software
remix-run
react-router
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-53667 is a CWE-79 (Improper Neutralization of Input During Web Page Generation) vulnerability in the remix-run react-router package. Specifically, in versions 7.11.0 through 7.17.0, the RSCErrorHandler component lacks protocol validation, which can lead to unsafe redirects from untrusted sources. This vulnerability only impacts applications that consume the unstable React Server Components (RSC) APIs. The issue was addressed and fixed in version 7.18.0.
Potential Impact
Successful exploitation can lead to high confidentiality impact by enabling attackers to redirect users to malicious sites, potentially leading to phishing or session hijacking. Integrity impact is low, and availability is not affected. The CVSS score is 6.9 (medium severity), reflecting network attack vector, high complexity, no privileges required, user interaction required, and scope change.
Mitigation Recommendations
Upgrade react-router to version 7.18.0 or later, where the vulnerability has been fixed. Since the issue only affects applications using the unstable RSC APIs, applications not using these APIs are not impacted. No other mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-09T20:50:36.877Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a67cc2f9c2644c7f8dbb22f
Added to database: 07/27/2026, 21:22:55 UTC
Last enriched: 07/29/2026, 23:54:59 UTC
Last updated: 09/10/2026, 20:01:52 UTC
Views: 102
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